<pre>

public class CustomMousePosition implements EntryPoint {

	private MapWidget mapWidget;
	private Map map;
	private WMS wmsLayer;

	public void onModuleLoad() {

		// First create map options.
		MapOptions mapOptions = new MapOptions();
		// you probably want to remove default controls
		mapOptions.removeDefaultControls();
		mapOptions.setNumZoomLevels(16);

		// Then create map widget and get map object.
		mapWidget = new MapWidget("350px", "350px", mapOptions);
		map = mapWidget.getMap();

		// Add some controls to the map
		map.addControl(new PanZoomBar());
		map.addControl(new LayerSwitcher());
		MousePositionOutput mpOut = new MousePositionOutput(){
			public String format(LonLat lonLat, Map map) {
				String out = "";
				out += "<b>This is the longitude </b> ";
				out += lonLat.lon();
				out += "<b>, and this the latitude</b> ";
				out += lonLat.lon();
				return out;
			}
		};
		MousePositionOptions mpOptions = new MousePositionOptions();
		mpOptions.setFormatOutput(mpOut); //rename to setFormatOutput
		map.addControl(new MousePosition(mpOptions));

		// Add a WMS layer
		WMSParams wmsParams = new WMSParams();
		wmsParams.setFormat("image/png");
		wmsParams.setLayers(ExampleConstants.METACARTA_WMS_BASIC_LAYER);
		wmsParams.setStyles("");

		WMSOptions wmsLayerParams = new WMSOptions();
		wmsLayerParams.setUntiled();
		wmsLayerParams.setTransitionEffect(TransitionEffect.RESIZE);

		wmsLayer = new WMS(
				"Basic WMS",
				ExampleConstants.METACARTA_WMS_URL,
				wmsParams,
				wmsLayerParams);

		// Add WMS layer to map
		map.addLayers(new Layer[] {wmsLayer});

		//Center and Zoom
		double lon = 4.0;
		double lat = 5.0;
		int zoom = 5;
		map.setCenter(new LonLat(lon, lat), zoom);

		DockPanel dockPanel = new DockPanel();
		dockPanel.add(mapWidget, DockPanel.CENTER);
		dockPanel.setBorderWidth(3);
		RootPanel.get().add(dockPanel);
	}
}

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